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Ladder Safety Calculator — 4:1 Ratio, Height & Footing Check

Check ladder setup safety: correct 4:1 angle (75 degrees), maximum height limits, 1m extension above landing point, and footing type assessment.

1m Extension Above Landing

Required for stepping on/off at top

How We Calculate This

This calculator checks ladder setup safety based on the 4:1 angle rule, height limits, and landing extension requirements per HSE guidance and the Work at Height Regulations 2005.

Safety checks

  • 4:1 ratio: Base distance = height ÷ 4 (gives 75° angle)
  • Extension: 1m minimum above landing point
  • Max height: 9m single, 15m extension, 4m stepladder
  • Ladder length: √(height² + base²) from Pythagoras

Frequently Asked Questions

Last updated: March 2026

All calculations are estimates. Verify with your supplier.